1. Technical Field
The present invention relates to illumination apparatuses provided with light-guiding plates and light-emitting elements, liquid-crystal display apparatuses provided with such illumination apparatuses, and electronic devices provided with such liquid-crystal display apparatuses.
2. Related Art
A liquid-crystal display apparatus provided with a transmissive type liquid-crystal panel includes, as shown in FIG. 8, an illumination apparatus 8 in which light-emitting elements 89 are disposed on a side end surface of a light-guiding plate 80 serving as a light entry portion 80a; meanwhile, optical sheets 180 and a liquid-crystal panel 10 are disposed in an overlapping manner on a light-emitting surface 80b side of the light-guiding plate 80. A light source substrate 88 provided with a mounting surface 881 orthogonal to the light entry portion 80a is used in this illumination apparatus 8, and in the case where a configuration in which the light-emitting elements 89 are mounted on the mounting surface 881 of the light source substrate 88, tilting in the optical axis of the light-emitting elements 89 causes the occurrence of illumination unevenness.
Accordingly, a configuration in which the light-guiding plate 80 and the light source substrate 88 are supported by a base plate portion 45 of a first frame 40 has been proposed (see JP-A-2004-273185).
Meanwhile, in the illumination apparatus 8 disclosed in JP-A-2004-273185, a configuration is employed in which the base plate portion 45 is recessed and a substrate support portion 456 is provided in a location that is lower than the surface of the base plate portion 45 that supports the light-guiding plate 80, and end portions of the light-guiding plate 80 partially overlap with the light source substrate 88.
However, according to the configuration illustrated in FIG. 8, at the ends of the light-guiding plate 80, there are areas where the first frame 40 overlaps with a rear surface 80c of the light-guiding plate 80 and areas where the light source substrate 88 overlaps with the rear surface 80c of the light-guiding plate 80; at these areas, the reflectance, degree of diffusion, and so on of the light differs. Accordingly, there is a problem in that illumination unevenness arises in the illumination light emitted from the light-guiding plate 80. Meanwhile, although there are cases where a reflective sheet 187 is provided on the rear surface 80c of the light-guiding plate 80, in such a case, the reflective sheet will warp due to height differences between a portion 187a of the reflective sheet 187 that makes contact with the base plate portion 45, a portion 187b of the reflective sheet 187 that overlaps with a gap, and a portion 187c of the reflective sheet 187 that makes contact with the light source substrate 88; this results in a problem in that illumination unevenness occurs.